Multiscale Engineered Si/SiO _x Nanocomposite Electrodes for Lithium-Ion Batteries Using Layer-by-Layer Spray...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Silicon-based anodes offer higher capacity than graphite for lithium-ion batteries but suffer from poor cyclability due to large volume changes.
• Silicon/silicon oxide (Si/SiO_x) nanocomposites show improved capacity retention by using amorphous SiO_x to buffer Si volume expansion.
• Current Si/graphite anodes are commercialized but limited by the usable fraction of Si due to cyclability issues.

Purpose of the Study:

• To develop an advanced electrode architecture for Si/SiO_x nanocomposite anodes.
• To improve the performance of Si/SiO_x anodes by addressing electrical contact and pulverization issues.
• To demonstrate a scalable fabrication method for the enhanced electrode architecture.

Main Methods:

• Fabrication of Si/SiO_x nanocomposite anodes using a scalable layer-by-layer atomization spray deposition technique.
• Incorporation of particulate carbon (C) interlayers between the current collector and the Si/SiO_x layer, and between the separator and the Si/SiO_x layer.
• Comparative analysis of the new electrode architecture against anodes with random material mixtures.

Main Results:

• The particulate C interlayers significantly improved electrical contact within the anode.
• The interlayers effectively reduced irreversible pulverization of the Si/SiO_x material during cycling.
• The multiscale approach (microstructuring and nanoengineering) resulted in enhanced capacity, rate capability, and cycling stability.

Conclusions:

• The novel electrode architecture with C interlayers offers a significant advancement for Si/SiO_x nanocomposite anodes.
• This approach effectively mitigates the challenges associated with Si volume expansion, leading to superior battery performance.
• The scalable spray deposition technique makes this advanced anode design potentially viable for commercial applications.